Physics…'Nuff Said

After a week or two of rigorous (and agonizing) attempts at getting a successful run at the Rube Goldberg machine, we have finally done it! With a total of 16 different simple machines, the task of pouring a cup of Kool-Aid is accomplished. This blog post shows the machine, and gives an analytical description of each component.

Here is an explanation of the machine at work:

Individual Machine Analysis:

Machine #1 (Water Hose) –
Our first machine involved the turning on of a water faucet, and the progression of water through a tube. A relatively simple way to start the machine. It is worth noting that the water pressure exerted from the faucet is greater than the pull of gravity, which allows the water to travel upwards through our loops of tubing. (It’s not everyday you see water run UP hill, do you?)

Machine #2 (Pulley System) –
The water from the first machine let out into a container. This container was attached to a pulley system, with a block of wood on the other side. In the beginning, the weight of the block exceeded the weight of the plastic container. However, as the water filled the container, the weight shifted. The end result was the block being lifted. This machine demonstrates how pulleys allow an object to be lifted rather easily. The string started with full tension on the block side. As the water filled the container, the tension started to balance out, and then continued to shift, until full tension was on the container side. By spreading out this tension across pulleys, it becomes easier to lift objects.

Machine #3 (Car on Ramp) –
The third machine came in the form of a car on a ramp. The ramp was tilted; the car barred by the wooden block. When the block was removed, gravity took hold of the car, and moved it down the track. The car then knocked a weight off the table. This machine is best for observing Newton’s Laws of Motions, especially the third one. Though our video doesn’t show it, the car recoiled backwards when it impacts the weight. This is due to the idea that every action has an equal and opposite reaction. Furthermore, the second law can be derived from this machine. Simply put, the force the car exerts is in the same direction that the car is accelerating (due to gravity). Direction is an important part of vectors, which is what the second law is all about.

Machine #4 (Trigger Pull) –
This machine is simple: the weight, falling off the table, pulls the trigger of a Nerf Gun. For this component, we used gravity to assist us (any object falling under the force of gravity only is known to be in free fall, by the way). The weight was one kilogram. We found through experimentation that this was heavy enough to cause a seemingly instantaneous tug on the string. As far as the Physics itself, the concept is simple: heavier objects fall with a greater force (please note that force and acceleration are two different things. All objects fall at the same rate of speed).

Machine #5 (Dart Shoots Hinge) –
The next machine involves the dart from the Nerf Gun hitting a “plate”, which is connected to a hinge. The hinge, which is positioned upright, falls downward onto the next step. For this, we relied on the idea that kinetic energy is transferred during collision. This idea goes hand in hand with the conservation of energy idea: the energy of the dart is not lost; rather, it transfers itself to the hinge, causing it to move.

Machine #6 (Death Car Down Track) –
The hinge would fall down into machine six, which would be pushing Death Car down a track. Death Car, so you know, is a hot wheels car with a razor blade attached to one end, and a small stir stick protruding out the other. The energy from the hinge (which, in turn, came from the dart) would be transferred to the car. The stir stick is what actually made contact with the hinge. We ensured the stick was incredibly rigid, because then the energy from the hinge would make the entire car “bounce”; dislodging itself from its place of resting. Also, Death Car started out with a large amount of potential energy: it was sitting in a high place. After we hit it, however, gravity started to take hold, and the potential energy converted to kinetic energy. We used this kinetic energy as a means of activating our next machine.

It is also worth mentioning that this machine helped us demonstrate inertia. If our car went down the track too fast (or if the track was too steep), then the car would fly off-course. This demonstrates the idea that an object in motion will continue to stay in motion. We had to ensure that our car was moving slow enough to allow gravity to dominate, and keep the car firmly on the track.

Machine #7 (Cutting String) –
As Death Car made its way down the track, it accelerated and gained momentum. At the end of the track was a balloon tethered to a thin string, right in the path of Death Car. The force of the razor blade’s inertia against the fibers of the string would cause shearing. The razor would hit the hard sheet metal we had braced to intercept it, sandwiching the soft string between two hard objects with great force. The energy that started with the air pressure to shoot a Nerf dart moved transferred from our hinge, now ends up dissipating as Death Car ends at the bottom of the track. However, the balloon whose string Death Car cuts continues the machine with it’s own momentum…

Machine #8 (Balloon Nudges Wood) –
The rising balloon would hit a small wooden stick hanging off the table. At the other end of the stick lies a small piece of Hotwheels track with a ball bearing attached. The stick functions as a first class lever, the edge of the table acting as the fulcrum, the upward force of the balloon adding effort to the system, and the track and ball bearing being the load. It’s worth noting that our lever behaved very strangely; the upward motion of the balloon sent the ball bearing moving downward, but since it was braced against the table, the only observable motion was a tiny nudge of the ball bearing. But this nudge is exactly what the machine was designed to create, since it would give the bearing enough motion to dislodge itself from the track.

Machine #9 (Ball Dislodges) –
The force of the lever causes motion on the Hotwheels track and the ball bearing resting on it. This side of the lever was elevated in order to let the stick’s downward motion have a greater effect on the track. The force of the balloon leaves the machine, and the force of gravity on the ball is what would move us forward from here.

Machine #10 (Ferris Wheel) –
The ball bearing would fall off the track and enter a long PVC tube. The tube opens out on a Ferris Wheel made of K’nex pieces. Taped to the wheel is a small plastic cup. The wheel is kept from spinning by a small wooden stick pressed against one of its spokes. The friction between the stick and the wheel keeps anything from moving, unless a force is applied downward on the wheel. The ball bearing lands in the cup and imparts its inertia onto the wheel. This impact allows the wheel to overcome the friction of the stick, and begin moving downward in the direction corresponding to the ball bearing. The circular momentum of the Ferris Wheel keeps it turning around the axle it’s bound to at the center, so the small force of the ball is enough to get the wheel turning.

Machine #11 (Baseball Rolls) –
Prior to the introduction of the ball bearing, a baseball would be sitting at the top of the Ferris wheel, balanced between it’s two top spokes. At its elevated position it has plenty of potential energy the machine can use. Once the wheel spins far enough so that what were once its top spokes begin facing downward, the baseball now feels the force of gravity on a inclined slope rather than a wedge. This change in position allows the ball the roll off the Ferris wheel, ready to impart the kinetic energy it gained from gravity to the next part of the machine.

Machine #12 (Target Practice) –
The baseball falls on and transfers its energy to our next contraption. It is a vertical metal rod with a supportive base to keep it upright. Attached to the middle of the rod is a yardstick. The yardstick is screwed loosely into the rod at its centerpoint, so it can function as a radial lever (if effort is applied up or down on one end, the yardstick will spin around the point it is screwed in at). The yardstick is tilted at about 70 degrees upward, the higher end facing the Ferris Wheel. Taped to the elevated end is a circular “target” of sorts. The baseball lands on this target, imparting its energy downwards onto the lever and making it spin…

Machine #13 (The Domino Effect) –
The next part of the machine is the perfect illustration of the Law of Conservation of Energy. The lever begins spinning as a result of energy the baseball provided it. As the lever spins, one end of the yardstick hits a domino with upward force. This causes the domino to tip over, transferring the energy it received from the lever to another domino in its path. As you may be able to guess, there is a long line of dominoes in front of the lever, waiting to be knocked over. In this way kinetic energy moves horizontally along the line of dominoes, each one forming a link in the chain. So, the potential energy of the elevated baseball, which became gravitational mechanical energy, traveled all the way across the room, into the machine at the end of the line of dominoes.

Machine #14 (Mouse-Trap Magic) –
The final domino in the sequence tips over and lands on an armed mouse trap. The metal lever of the trap is attached to a string, which goes from the trap on the floor, up to a small, upright piece of wood on a table. The wood is supporting a tray of marbles, which we’ll discuss later. As the domino hits the trap, the potential energy of the tension within the trap is release, and the metal lever snaps downward. The force of the snapping, as well as the few inches of movement the lever exhibits, pulls on the already taught string connected to the wooden stick, forcing the stick itself to move…

Machine #15 (Running of the Marbles) –
As stated earlier, the mouse trap is connected to a tray lined with marbles. Many marbles. Lots and lots of marbles. I don’t think you understand…SO MANY marbles (or at least it seemed that way when they all spilled)…

Anyway, the activation of the mouse trap caused the wood supporting the front of the tray (the back was elevated with books) to fall two or three inches. This is enough of an incline for the marbles to roll off the tray and down an extremely large track. This machine once again shows us the law of inertia. The removal of the wood piece was sudden enough that – for a split second (unseeable on the video) – the tray remained elevated (an object at rest stays at rest). Only when gravity “took hold” did the tray fall. It is the same concept as the pulling off of a table cloth without disturbing the plates on top of it. We know this occurred because, if the wooden piece was removed any slower, the tray would buckle, tilt, or do anything but fall straight; it would be moved with the wooden piece. The rest of the machine is merely gravity at work (gravity is what turns the potential energy of the marbles into kinetic energy). The marbles gained momentum as they rolled down the track: you can see this in the video when the marbles turn the corner and some “jump” out; a product of the energy in the marble experiencing the sudden stop that is the corner. It is this momentum that helped us give our next machine a little extra “umph”.

Machine #16 (Kool-Aid Dispensary) –
The last machine in our contraption involved a bag resting above a syringe, which in-turn was resting above a cup. The marbles from the previous step would be funneled into the bag. The accumulated weight from the marbles, thanks once again to our friend gravity, was enough to push the syringe downward – thereby filling our cup with Kool-Aid. We analyzed the workings of a syringe when it came time to apply the scientific, analytical perspective to our machine. When you fill a syringe with a substance, in our case Kool Aid, the substance exerts a force on every wall of the syringe. The amount of force is dependent upon temperature and pressure (the latter, of course, is obtained by changing volume). The external force pushing on the syringe, which is air, is not greater than the force that the Kool Aid is pushing back. Therefore, the syringe doesn’t compress on its own. But, by adding the weight of a bunch of marbles, the external force becomes greater than the internal force that the liquid is pushing the syringe back with. This results in the Kool Aid leaving the syringe. Who knew such a simple device could have so much physics behind it?

When all the components listed above come together, they create a (rather impressive, if we do say so ourselves) working Rube Goldberg Machine! Here is a video showing each step activating in succession during one run through. In short: here is a video of our success! It finally worked! Enjoy!

Within the last month and a half we had created a prairie dog trap. We attempted to create the “box trap” because there was a need for it in our community church for a spoof play that they were presenting for a fund raiser to help with the mission trip they were going on. The trap took us about a month to develop. That included the plan and design and the building. When building the trap there was lots of wood that we happen to use. We would use plywood as a bottom base to help keep the trapped in4/4. We had this bottom because of the fact that prairie dogs can dig, so that was used to prevent that. 2/4’s, 2/6’s and also we used to make the top part. We made something like a box but the bottom was the large platform. Using chicken wire was handy just so that way it made it more realistic trap. We made it so that way it was like an alligators mouth. Then the prairie dog would inter the trap then it would close down. The hinges is what made that possible. Some of our struggles were that we couldn’t decide on a way to make the trap shut. There is so many ways that the trap couldn’t of been sprung. We wanted to go with a pulley way. What we did was tied a rope on a 2/4 that held the upper part of the trap up. We were able to pull it with the rope to make it close. This happen to be useful, and highly affective. The trap was a success and we had a lot of fun and helped out the church!

In this project another group decided to try and make a lava lamp using alka seltzer and vegetable oil and water and food dye. They allowed us to piggy back along and help out. So what was happening was there was a two leter bottle that we took and filled it halfway with water then took food coloring and put vegy oil in the other half then inserted alka seltzer tablets and as they fizzed they made water bubbles that were colored push up into the oil then go back down sense the water separated and sat below the oil. The problems that we had challenged in this project was there weren’t enough supplies so we had to down grade bottles to a smaller one which led to a gatorade bottle. Then we ran out of oil so we had to go and borrow more from the kitchen. Then we almost ran out of food coloring but mrs.Roberson is nice enough to lend us some of hers that she had in her room. This project was fun and it was really cool to see the water balls move through the oil like that.

The next project we helped with was the blowing up of a bottle. We used vinegar, baking powder and some alka seltzer. We took a 2 leter bottle and went outside and mixed them into the bottle and placed it in the parking lot. Then we noticed that the bottle stopped making pressure and didn’t explode. This sucked so we had to go out and throw the bottle around until it kept making pressure. Well it started hissing and i took it and threw it up and it hit the ground blew off the cap and then blasted off faster than anyone expected it to. It went so fast that if you weren’t paying attention to the bottle or blinked you would have missed it. This is always a fun project to do because it involves some sort of boom. I had a lot of fun being apart of this project.

With this project, which we didn’t Finnish, the plan was to pick out every form of science type of adventure within the episodes. There was things from portal gun, dream time travel, and some other fun science types like that. One thing that we know of would happen to be the dream travel. The explanation that was told within the show was that, if you were to go into a dream the time would slow down 100 tenths of a second. Rick and Morty would go in to dream then into another dream within the current dream that they are in. Time in the first dream was at no motion or slowed down a lot. The first dream which was the objective in the first place was slowed down to 400 times a second, they used this amount of time to fix problems that Mortys father had produced. That is as far as we had got with the project. We had published it to youtube but within the process it had gotten ruined and the video no longer plays as of where it stands. It was enjoyable and there was a lot of fun within doing this project.

The last part of this year our group has created many projects: air pressure cork gun, lava lamps, pressurized bombs, magnets, electric door bell, and we launched rockets. We ended the last semester trying to create a computer programed piano with infrared lights, the first part of this year went to finishing that, it is now a fully operational piano with 8 notes. After that we decided to go back to a more violent set of experiments. We began fairly tame with experimenting with creating magnets out of nails, copper wire, and a battery; we ended up making pretty weak magnets, but it did propel us into our next experiment which was messing with electrical currents. Our big experiment with electric currents was creating a door bell that was electric powered, the bell was operated with a push button that opened and closed a current that would ring the bell. Then we began to mess with air pressure, we started with the rocket launcher in the storage room, we made some fabrications (duct tape and a PVC pipe) to make the launcher longer and we found corks that would fit the PVC pipe, the result: a fully operational air pressure cork gun. Then we decided to mess with pressurizing sealed containers like bottles until they exploded, we did this with vinegar and baking soda, or alka seltzer. Finally, we ended by making lava lamps with water, food color, vegetable oil, and alka seltzer. The lava lamps were created when the denser water that was dyed with food color produced bubbles due to the alka seltzer and passed through the less dense layer of oil on top.

This is what our lava lamp looked like

This is our air pressured cork gun.

This is us filling an empty bottle with baking soda and vinegar.

These are pictures of our programmed piano.

My contribution to these projects was: I aided in the programming of the computer, I built the cork gun with duct tape and PVC, I found the ideas for the lava lamps and gathered the materials and made them, made the idea of making the pressurized bombs with baking soda, vinegar, and alka seltzer.

So, as the year is wrapping up, it has come to our attention that we should make THE ENTIRE WORLD aware of all the awesome things we have done in Physics this year. I have kept you guys pretty updated with everything I have done so far. We spent most of our time first semester playing with a quadcopter that to this day I still curse! Stinking thing will never work… Then, when second semester started, I started to work on some projects on my own. My first project was a mobile, which took WAY LONGER than it ever should have, but that is because I wasn’t quite getting the big picture! To see everything about that project, you can look at these 123 blog posts (p.s. each number is a different blog post (: )! Then after that I did some fun stuff with waves, which is what I will be talking about now.

As I was searching for another project to do, I kept thinking about pendulums and was curious if I could do anything with that. Luckily for me, that is when my brilliant teacher came to my rescue and gave me an idea–to create waves with a pendulum, some sand and a piece of paper. How does this work? Well, let me tell you! So I set up a nice little rig including a ring stand and a plastic syringe that had been a little cut up. Basically, the syringe had the tip cut of so that there was a tiny hole in the bottom and it also had the top bulb cut in half so you could put something inside the syringe. I then tied the syringe to the edge of the ring stand and it swung pretty well (at least well enough to make waves on 8 inch wide papers). The next step was to put some sand (at first is was dirt and magnetic filings, but that didn’t work so well) in the syringe, so that as the syringe swung, something would track the path it takes. So about now you are probably wondering how this makes a wave instead of a giant pile of sand. Well, the solution to the potential of mini sand dunes is simple–move the paper! Once you move the paper sideways while the pendulum is swinging, you get WAVES! They look a little like this…

As you can see the beginning of the wave is a little iffy, and that is purely because I don’t understand how to swing things. But it straightened out eventually and made some pretty decent little waves. So then I experimented a little bit with how fast I would move the paper, seeing as how that would affect the wavelength. HYPOTHESIS: If I slow down the movement of the paper then the wavelength will be shorter because there is less distance for the waves to travel in a certain amount of time. Contrarily, if I speed up the movement of the paper, the wavelengths will be longer because they cover more distance in a certain amount of time. I know, it seems like a pretty basic process but, I figured it is science either way you swing it (haha did you see what I did there…)!

So, moving back to the point, here is a picture of the waves when I slowed down the paper.

So, MY HYPOTHESIS WAS CORRECT! Not that it makes me an evil genius or anything because it is a little bit of common sense, but yeah. So the wavelengths definitely were shorter! So, lets see if my hypothesis stands for speeding the paper up…

And it does! TOUCH DOWN! Like I said, this project was little bit of common sense, but it was still fun to do. Plus, I didn’t even realize you could make waves with a pendulum and some paper! It was enjoyable to be able to play around with waves, after all they are in our everyday lives! Either way, I hope you liked my little, silly blog post! And maybe someone will do this project again some day and probably be a little more creative!

P.S. I apologize for the caps and bolding throughout! I think it is a symptom of Senioritis, seeing has how we have 3 DAYS LEFT!